Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts: Gene/Protein Disease Symptom Drug Enzyme Compound   Target Concepts: Gene/Protein Disease Symptom Drug Enzyme Compound

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Query: EC:3.2.1.20 (alpha-glucosidase)
4,237 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Since they are found to be increased in lesions of acute necrotic ulcerative gingivitis or marginal periodontitis, agents for these diseases. In the present study, 38 pure cultured strains were obtained as a result of isolation and culture of samples collected from lesions of marginal periodontitis (periodontal pokets), and the biological and biochemical characteristics of these strains were investigated. 1) Light microscopy (including dark-field microscopy) and transmission electron microscopy (negative staining) were used for observation of the morphology and cellular structure of the strains. The cells had a spiral shape, and showed active movement. Based on the above findings the cultured strains were all confirmed to be spirochetes of small to medium size, being 0.08-0.24 micron in width. 2) Growth and motility of the strains were investigated on various types of culture medium. Intense growth and movement were noted in strains cultured in bovine liver exudate medium containing horse serum (pH 7.2) at 37 degrees C under anaerobic conditions produced by the evacuation-replacement method (95% N2, 5% CO2) for 3-7 days after inoculation. 3) Thirty-five strains were positive for indole production and decomposition of urea, mucin, hippuric acid and esculin. Production of hydrogen sulfied was observed in 31 strains. In decomposition tests for 17 carbohydrates, 17 strains were positive for galactose and 14 strains were positive for glucose, while 11 strains were positive for dextrin and 10 strains for fructose upon decomposition of soluble starch. Other carbohydrates were also decomposed by a few strains. 4) In an investigation of the production of alcohol and lower fatty acids, among the metabolic products detected by gas chromatography, a large amount of acetic acid and small amounts of ethanol, lactic acid, propionic acid, pyruvic acid were observed. 5) The results of enzyme activity tests using an API ZYM system indicated relatively high activities of esterase, esterase-lipase, alpha-glucosidase, alkaline phosphatase, trypsin and acid phosphatase.
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PMID:[Biological and biochemical characteristics of the oral spirochetes isolated from the focus of marginal periodontitis]. 276 48

A previous study has shown that long-term feeding of ethanol in high doses (36% of total calories) causes marked changes in intestinal mucosal disaccharidase activity as well as blunting of the intestinal villi. To determine whether similar damage occurs in response to a more moderate ethanol exposure, we pair fed rats a liquid diet that provided 15.5% of total calories from ethanol for 5 weeks. In the proximal segment of the intestine, we found that ethanol did not affect the total activities of maltase (8.0 +/- 2.4 U vs. control value of 6.7 +/- 1.8 U), sucrase (1.5 +/- 0.5 U vs. control of 1.2 +/- 0.3 U), or lactase (125 +/- 42 mU vs. control of 107 +/- 36 mU). Similarly, we found no differences from control values for the three disaccharidases in the middle or distal small bowel. The mucosal protein content of the experimental animals did not differ from values found in the control animals. In addition, no change in intestinal villus height or crypt depth was detected. The zinc content of hair and serum was not affected by the ethanol feeding. We conclude that prolonged ingestion of a moderate dose of ethanol does not damage the small intestinal disaccharidase enzymes, mucosal protein content, or intestinal architecture.
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PMID:Effect of moderate prolonged ethanol ingestion on intestinal disaccharidase activity and histology. 308 74

Rat intestinal microvillus maltase-glucoamylase was isolated by detergent extraction and purification in the presence of protease inhibitors as previously described and incorporated into phospholipid vesicles. After purification of the vesicles on Sephadex G-50, maltase was labelled with 3-trifluoromethyl-3-(m-[125I]iodophenyl) diazirine ([125I]TID) by photolysis using a water-jacketed mercury vapour lamp with a saturated CuSO4 filter. The labelled enzyme was extracted with acetone, resuspended in 1% Triton X-100, reincorporated into phospholipid vesicles, and digested with activated papain to release the hydrophilic polar head of the enzyme from the vesicle bilayer. Vesicle-bound and free enzyme components were separated on Sepharose 4B. Ninety percent of the enzymatic activity was free, while a similar percentage of radioactive label remained with the vesicles in keeping with the separation of an active polar headpiece from a labelled apolar peptide in the lipid bilayer. The vesicle fractions were subjected to chromatography on Sephadex LH-60 with ethanol--formic acid (7:3) as the eluant. A single radioactive peak (14 kilodaltons (kDa)) was separated from labelled lipid. Sodium dodecyl sulfate--polyacrylamide gel electrophoresis of the peak showed a radioactive doublet of 26-28 kDa, possibly representing a dimer. No other labelled peptides were found. These results suggest that detergent-solubilized maltase-glucoamylase is inserted into the phospholipid bilayer via an apolar peptide with a minimum molecular mass of 14 kDa. The peptide probably represents a terminal anchor segment of the 145-kDa subunit which is converted to 130 kDa when the membrane-bound enzyme is solubilized by papain.
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PMID:Hydrophobic binding domains of rat intestinal maltase-glucoamylase. 309 59

1. Ram seminal plasma alpha-glucosidase has been purified in order to increase our knowledge of this enzyme and of its role in epididymal physiology. 2. Since the enzyme behaved differently from other known acid alpha-glucosidases and was not affinity-adsorbed on dextran gels, another approach had to be used. 3. The final procedure included an ethanol precipitation step, sequential chromatography on hydroxylapatite and DEAE Sepharose CL-6B, isoelectric focusing in polyacrylamide gels and ultrafiltration. 4. The resulting purification factor of alpha-glucosidase was 9822 with an overall yield of 5%. 5. The purified material consisted of several isoforms with a mol. wt of 105,000 and isoelectric points varying between 4 and 5.
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PMID:Purification of ram seminal plasma acid alpha-glucosidase. 312 30

The effect of the glucose analogue 5-thio-D-glucose (5TG) on the yeast Saccharomyces cerevisiae was studied. Derepression of mitochondrial respiratory chain cytochromes, alcohol dehydrogenase (isoenzyme II), NADH dehydrogenase and maltase was inhibited by 0.5-2 mM-5TG. Growth rate was only slightly affected. Ethanol was efficiently produced with 2 mM-5TG in medium initially containing 0.25% glucose. Mutants resistant to the growth inhibitory effects of 5TG on glycerol medium showed resistance to the catabolite repressing effects of glucose. Other mutants, known to be catabolite repression resistant, showed resistance to 5TG. The analogue seems to inhibit derepression of glucose repressible enzymes with greater potency than glucose itself.
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PMID:Catabolite repressive effects of 5-thio-D-glucose on Saccharomyces cerevisiae. 330 35

Clostridium thermosulfurogenes displayed faster growth on either glucose, maltose, or starch than Clostridium thermohydrosulfuricum. Both species grew faster on glucose than on starch or maltose. The fermentation end product ratios were altered based on higher ethanol and lactate yields on starch than on glucose. In C. thermohydrosulfuricum, glucoamylase, pullulanase, and maltase were mainly responsible for conversion of starch and maltose into glucose, which was accumulated by a putative glucose permease. In C. thermosulfurogenes, beta-amylase was primarily responsible for degradation of starch to maltose, which was accumulated by a putative maltose permease and then hydrolyzed by glucoamylase. Regardless of the growth substrate, the rates of glucose, maltose, and starch transformation were higher in C. thermosulfurogenes than in C. thermohydrosulfuricum. Both species had a functional Embden-Meyerhof glycolytic pathway and displayed the following catabolic activities: ferredoxin-linked pyruvate dehydrogenase, acetate kinase, NAD(P)-ethanol dehydrogenase, NAD(P)-ferredoxin oxidoreductase, hydrogenase, and fructose-1,6-diphosphate-activated lactate dehydrogenase. Ferredoxin-NAD reductase activity was higher in C. thermohydrosulfuricum than NADH-ferredoxin oxidase activity, but the former activity was not detectable in C. thermosulfurogenes. Both NAD- and NADP-linked ethanol dehydrogenases were unidirectional in C. thermosulfurogenes but reversible in C. thermohydrosulfuricum. The ratio of hydrogen-producing hydrogenase to hydrogen-consuming hydrogenase was higher in C. thermosulfurogenes. Two biochemical models are proposed to explain the differential saccharide metabolism on the basis of species enzyme differences in relation to specific growth substrates.
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PMID:Differential amylosaccharide metabolism of Clostridium thermosulfurogenes and Clostridium thermohydrosulfuricum. 393 39

1. The maltase, sucrase, isomaltase and palatinase activities of the chick small intestine are localized in particles that sediment when centrifuged at 100000g for 90min. 2. Solubilization of the particle-bound disaccharidases without loss of activity was achieved by digestion with papain. Trypsin was less effective and caused a preferential solubilization of the sucrase, isomaltase and palatinase activities. 3. On Sephadex G-200 columns, the solubilized preparations yielded two disaccharidase peaks. The first peak was eluted close to the void volume of the column and contained all the sucrase, isomaltase and palatinase activities and some of the maltase activity. The remainder of the maltase activity was eluted beyond the total volume of the column. 4. Precipitation with ethanol did not affect the behaviour of the disaccharidases of gel filtration. 5. The maltase activity of the second peak on rechromatography in a buffer containing 0.01m-maltose was eluted close to the void volume. 6. Similar pH optima but different K(m) values were obtained for the maltase activities of the two peaks. 7. Heat-inactivation studies showed that the first peak contained two disaccharidase enzymes; one hydrolysed sucrose and maltose and the other hydrolysed isomaltose, palatinose and maltose. The second peak contained three disaccharidase enzymes all specific for the hydrolysis of maltose. 8. It is proposed that the intestinal disaccharidases of the chick exist in the form of two complexes: a sucrase-isomaltase complex and a maltase complex.
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PMID:Heat inactivation and sephadex chromatography of the small-intestine disaccharidases of the chick. 541 28

1. The maltase, isomaltase and invertase (sucrase) activities of solubilized mucosal preparations from human jejunum and ileum were studied with column chromatography on anion-exchange (diethylaminoethyl- and triethylaminoethyl-)cellulose and Sephadex G-200 gel. 2. On ion-exchange cellulose columns both kinds of enzyme preparations yielded two major disaccharidase peaks. The first peak contained maltase Ia (=isomaltase) and maltase Ib (=invertase). The second peak contained maltase II and maltase III. 3. On Sephadex G-200 gel columns jejunal preparations yielded the corresponding peaks as on ion-exchange columns, but the peaks appeared in the reverse order in the effluent. The ileal preparation studied yielded a single peak on gel columns, containing all the activities studied and eluted with the ;void volume'. 4. Precipitation with ethanol did not affect the behaviour of the enzymes during ion-exchange chromatography. When gel filtration was performed after ethanol precipitation of the enzymes, however, two peaks were obtained also with the ileal preparation, and subfractionation of the invertase was obtained with both kinds of preparations. 5. The second peak from ion-exchange chromatograms, containing maltase II and maltase III, on concentration was found to have very weak isomaltase activity, probably exerted by these enzymes as such. This activity accounts for only about 1% of the total isomaltase activity of the mucosa. 6. The results support the concept of the specificity of the human small-intestinal disaccharidases previously described after heat-inactivation experiments. The subfractionation of the invertase that under certain conditions is seen on Sephadex G-200 columns appears most likely to be an artifact. Consequently the nomenclature for the human maltose-, isomaltose- and sucrose-splitting enzymes proposed by another research group after gel-filtration chromatography studies should be abandoned. It seems more logical to keep the nomenclature based on heat inactivation [maltase Ia (=isomaltase), maltase Ib (=invertase or sucrase), maltase II and maltase III] until increased knowledge about the specificity and structure of these enzymes makes possible a more rational nomenclature.
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PMID:Column chromatography of human small-intestinal maltase, isomaltase and invertase activities. 576 86

A selection system has been devised for isolating hexokinase PII structural gene mutants that cause defects in carbon catabolite repression, but retain normal catalytic activity. We used diploid parental strains with homozygotic defects in the hexokinase PI structural gene and with only one functional hexokinase PII allele. Of 3,000 colonies tested, 35 mutants (hex1r) did not repress the synthesis of invertase, maltase, malate dehydrogenase, and respiratory enzymes. These mutants had additional hexokinase PII activity. In contrast to hex1 mutants (Entian et al., Mol. Gen. Genet. 156:99-105, 1977; F.K. Zimmermann and I. Scheel, Mol. Gen. Genet. 154:75-82, 1977), which were allelic to structural gene mutants of hexokinase PII and had no catalytic activity (K.-D. Entian, Mol. Gen. Gent. 178:633-637, 1980), the hex1r mutants sporulated hardly at all or formed aberrant cells. Those ascospores obtained were mostly inviable. As the few viable hex1r segregants were sterile, triploid cells were constructed to demonstrate allelism between hex1r mutants and hexokinase PII structural gene mutants. Metabolite concentrations, growth rate, and ethanol production were the same in hex1r mutants and their corresponding wild-type strains. Recombination of hexokinase and glucokinase alleles gave strains with different specific activities. The defect in carbon catabolite repression was strongly associated with the defect in hexokinase PII and was independent of the glucose phosphorylating capacity. Hence, a secondary effect caused by reduced hexose phosphorylation was not responsible for the repression defect in hex1 mutants. These results, and those with the hex1r mutants isolated, strongly supported our earlier hypothesis that hexokinase PII is a bifunctional enzyme with (i) catalytic activity and (ii) a regulatory component triggering carbon catabolite repression (Entian, Mol. Gen. Genet. 178:633-637, 1980; K.-D. Entian and D. Mecke, J. Biol. Chem. 257:870-874, 1982).
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PMID:Saccharomyces cerevisiae mutants provide evidence of hexokinase PII as a bifunctional enzyme with catalytic and regulatory domains for triggering carbon catabolite repression. 637 Sep 59

The effects of prolonged alcohol administration were studied on the brush border enzyme activities of the jejunum in rats receiving either a normal laboratory diet or a high carbohydrate-low protein for several weeks. Alcohol (15%) given in association with the normal diet provoked a stimulation of sucrase, maltase, and lactase activities after four weeks, but no significant modification in aminopeptidase activity. These results obtained for the disaccharidases were very similar to those observed with the high carbohydrate-low protein diet given without alcohol, although major differences were obvious in the timing of enzyme stimulation. In contrast, this dietary condition initiated a drop in aminopeptidase activity. When alcohol was given in association with the high carbohydrate-low protein diet, no modification in aminopeptidase activity was detected and the stimulation for the disaccharidase activities was similar to that observed with the high carbohydrate-low protein diet given alone. The present results suggest that the mechanisms involved in the stimulation of brush border disaccharidase activities were different for alcohol and for the high carbohydrate-low protein diet.
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PMID:Effects of prolonged alcohol administration and a high carbohydrate-low protein diet on the activities of the jejunal brush border enzymes in the rat. 681 99


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